HI,I have updated my iPhone 6 to latest iOS 11.3.1I am using Zimbra 8.7.11_GA_1854 FOSSSince the upgrade I can no longer send email from my iPhone although I can receive it.I have tried setting up account as IMAP and also as Exchange but neither setup allows sending.I get the message fred@fred.com was rejected by the server.These are the same credentials as used by my android tablet which works.

I tried various "fixes" for the last couple of weeks but to no avail.Appreciate any suggestions.Thanks and kind reagrds,

jB PS Anyone know how to upgrade Zimbra to latest version all I can read about says it is impossible without major work????